This is blatantly untrue to the level of fear mongering. The politician can’t do whatever he wants. The election simply moves from republican candidate against

This is blatantly untrue to the level of fear mongering. The politician can’t do whatever he wants. The election simply moves from republican candidate against democrat candidate to the primaries where the top 3 politicians from the dominant party are running against one another for the nomination. If they adopted policies the majority of their party didn’t like they would be replaced by another member of the party in the next election.